Re: [TLS] Consensus for AEAD IV

Eric Rescorla <ekr@rtfm.com> Sun, 17 May 2015 13:28 UTC

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From: Eric Rescorla <ekr@rtfm.com>
Date: Sun, 17 May 2015 06:27:43 -0700
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To: Joseph Salowey <joe@salowey.net>
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Subject: Re: [TLS] Consensus for AEAD IV
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The following PR makes this change:
https://github.com/tlswg/tls13-spec/pull/155

Target merge date: 5/20


Note 1: I haven't done anything about changing derivation one way or the
other. These are orthogonal issues.

Note 2: Should the ChaCha draft adopt this change as well, since it's
already incompatible with the encoding TLS 1.2 uses for GCM?

-Ekr


On Fri, Apr 24, 2015 at 10:10 AM, Joseph Salowey <joe@salowey.net> wrote:

> The general consensus on the list seems to prefer to derive "IV" and use
> it to make the AEAD nonce less predictable. Most folks seemed to be OK with
> this approach.    In Dallas, there was significant support for using the
> derived "IV" as a per session XOR mask for the counter.  If you have
> objections to this approach please respond on the list by May 1, 2015 .
>
> Cheers,
>
> Joe
>
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